As technologies progress, the technical level and products in the mechanical manufacturing industry are upgraded continuously. The competition among mechanical manufacturer worldwide becomes harsh. Consequently, to maintain competitiveness and exploring new and developing markets, in addition to uninterrupted development of new products and technologies for increasing revenues, during the manufacturing process, mechanical manufacturers should also improve the accuracy, production yield, and efficiency of products.
To improve the accuracy, production yield, and efficiency of products, in addition to developing machine tools that manufacture products, during the manufacturing process of machine tools, the measurement techniques for errors of the machine tools must follow the progress of the machine tools, so that high-precision machine tools can have high-precision measurement techniques for inspecting or compensating their error in the ex-factory calibration stage. Thereby, the production yield and efficiency of products can be enhanced.
Currently, the optical equipment is applied to measuring errors of machine tools. The representative equipment is the laser interferometer. While measuring errors using a laser interferometer, a laser beam is divided into two and reflected by corresponding mirrors. During the reflection process, the two laser beams interfere with each other. By analyzing the acquired interference graph, the errors of a platform can be calculated. Unfortunately, most laser interferometers can measure only one error at a time. Thereby, to measure multiple errors, it is unavoidable to perform multiple measurements. In the process, undoubtedly, much time will be wasted and the speed for ex-factory calibration will be decreased drastically. Moreover, laser interferometers are costly. If one machine tool should include a laser interferometer for measuring errors, the cost of products will be increased.